Kakuro

Language:

4x4: easy intermediate hard challenging expert
6x6: easy intermediate hard challenging expert
8x8: easy intermediate hard challenging expert
9x11: easy intermediate hard challenging expert
9x17: easy intermediate hard challenging expert

Kakuro is like a crossword puzzle with numbers. Each "word" must add up to the number provided in the clue above it or to the left. Words can only use the numbers 1 through 9, and a given number can only be used once in a word. Every kakuro puzzle has one and only solution, and can be solved through logic alone.

Kakuro Blog
Kakuro Rules
Kakuro Tutorials: Basic Challenging

Kakuro Hint: Start with clues that only have one valid combination. For example, 3 in 2 must be 1 and 2, and 23 in 3 must be 6, 8, and 9.

		30	13		9	13		8	19
	8 20			7 13			3
25							10 11
4			6 30			17 22
28					13 13			24	9
24				32
	17			17 12
	13	12 24					5 11
17			11 3			4 21			10
11					16 19
	5 21			9			12 26
14			18	12 19				26
31						8			20
17						11 7
	20	11 12			16 7
13				3 15			14 6
16			30
12			10			13

Free online kakuro puzzles